白洋淀湿地典型植被芦苇储碳固碳功能研究

Carbon Storage and Fixation Function by Phragmites australis,a Typical Vegetation in Baiyangdian Lake

湿地生态系统具有很强的储碳、固碳能力,在全球碳循环中占有重要地位。在实地调查和实验室测定的基础上,研究了白洋淀湿地芦苇(Phragmites australis(Cav.)Trin.Ex Steudel)的现存生物量和初级生产,并根据光合作用原理测算了其碳储量和固碳能力,进而从光能利用率的角度探讨了其固碳潜力。结果表明,白洋淀湿地芦苇的碳储量较大,为2.52～3.44kg.m-2,平均2.9kg.m-2,且地下部分的生物量大于地上部分,两者比值为2.38～3.30,平均2.90,地下部分碳储量是地上部分的近3倍。白洋淀湿地芦苇具有较强的固碳能力,为0.82～1.65kg.m-.2a-1,是全国陆地植被平均固碳能力的1.7～3.4倍,全球植被平均固碳能力的2.0～4.0倍。白洋淀湿地芦苇的光能利用率仅为0.6%～1.2%,若提高到植物理论最大光能利用率5%～6%,则固碳能力可较目前提高3.2～9.0倍,达到6.60～8.25kg.m-.2a-1,潜力很大。

Wetland ecosystems have strong ability for carbon storage and fixation, and play important roles in the global carbon cycle. To understand carbon storage and fixation conditions of Phragmites australis （Cav.）Trin. Ex Steudel in Baiyangdian Lake, a typical wetland ecosystem, field investigation was conducted on P.australis biomass and net primary productivity, followed by laboratory measurements. In accordance with the theory of photosynthesis, carbon storage and fixation by P.australis in the wetland were estimated. Potential carbon fixation of the vegetation was also discussed according to light efficiency. Results showed a great carbon storage in the typical wetland ecosystem of Baiyangdian Lake （2.52-3.44 kg·m^-2）, at an average of 2.9 kg·m^-2. Root biomass was larger than shoot biomass, and the ratio was about 3 （2.38-3.30, at an average of 2. 90）. Thus mot carbon storage was about 3 times that of shoot. A typical wetland like that of Baiyangdian Lake had a strong carbon fixation ability, 0.82-1.65 kg·m^-2·a^-1; could be 1.7-3.4 times of the average carbon fixation of terrestrial vegetations in China, and 2.0-4.0 times of that of the world. According to the formula of light efficiency, it was still low, only 0.6%-1.2%. If the light effi- ciency were improved to be 5%-6%, the maximum in theory, the carbon fixation ability of the vegetation in the wetland would increase 3.2- 9.0 times and reached 6.60-8.25 kg·m^-2 per year, the potential carbon fixation would be huge.